Faculty of Pharmacy, University of Sydney, Sydney, NSW, 2006, Australia.
Microb Ecol. 2012 Aug;64(2):431-49. doi: 10.1007/s00248-012-0044-8. Epub 2012 Mar 21.
The bioactive compounds of medicinal plants are products of the plant itself or of endophytes living inside the plant. Endophytes isolated from eight different anticancer plants collected in Yunnan, China, were characterized by diverse 16S and 18S rRNA gene phylogenies. A functional gene-based molecular screening strategy was used to target nonribosomal peptide synthetase (NRPS) and type I polyketide synthase (PKS) genes in endophytes. Bioinformatic analysis of these biosynthetic pathways facilitated inference of the potential bioactivity of endophyte natural products, suggesting that the isolated endophytes are capable of producing a plethora of secondary metabolites. All of the endophyte culture broth extracts demonstrated antiproliferative effects in at least one test assay, either cytotoxic, antibacterial or antifungal. From the perspective of natural product discovery, this study confirms the potential for endophytes from medicinal plants to produce anticancer, antibacterial and antifungal compounds. In addition, PKS and NRPS gene screening is a valuable method for screening isolates of biosynthetic potential.
药用植物中的生物活性化合物是植物本身或内生真菌的产物。从中国云南采集的 8 种不同抗癌植物中分离出的内生真菌，其 16S 和 18S rRNA 基因系统发育多样。本研究采用基于功能基因的分子筛选策略，针对内生真菌中的非核糖体肽合成酶（NRPS）和 I 型聚酮合酶（PKS）基因。对这些生物合成途径的生物信息学分析有助于推断内生真菌天然产物的潜在生物活性，表明分离出的内生真菌能够产生大量的次生代谢产物。至少在一项测试中，所有内生菌培养物提取物均表现出抗增殖作用，无论是细胞毒性、抗菌还是抗真菌作用。从天然产物发现的角度来看，本研究证实了药用植物内生真菌产生抗癌、抗菌和抗真菌化合物的潜力。此外，PKS 和 NRPS 基因筛选是筛选生物合成潜力菌株的一种有价值的方法。
